Generally, terminals can be classified as mobile/portable terminals and stationary terminals according to their mobility. The mobile terminals can be further classified as handheld terminals and vehicle mount terminals according to possibility of user's direct portability.
Mobile terminals have become increasingly more functional. Examples of such functions include data and voice communications, capturing images and video via a camera, recording audio, playing music files via a speaker system, and displaying images and video on a display. Some mobile terminals include additional functionality which supports game playing, while other terminals are configured as multimedia players. More recently, mobile terminals have been configured to receive broadcast and multicast signals which permit viewing of content such as videos and television programs. In order to perform the aforementioned functions, basically, a mobile terminal is connected with different devices or a network using various communication protocols and may be able to provide ubiquitous computing environment to a user. In particular, the mobile terminal is evolving to a smart device enabling connectivity to a network and ubiquitous computing.
Conventionally, the smart device as the mobile terminal has been manufactured by a size capable of being held by a hand of a user and the user used to carry the smart device by hand or put in a bag or a pocket. Yet, with technological advances, the smart device is manufactured by a smaller size and is evolving to a wearable device directly worn on a body of a user. In particular, among wearable smart devices, a smart watch capable of being worn on a wrist of a user has been recently developed and is widely used.
The smart watch has been developed to provide not only a function of a general watch (e.g., time information) with a wearable small size but also various and enhanced functions as a mobile terminal. A recently developed smart watch has almost all functions of the previously mentioned mobile terminal to enable the mobile terminal to be replaced with the smart watch. Meanwhile, since a user is able to conveniently carry a smart device, the user frequently uses a camera of the smart device to obtain image information, i.e., to capture a picture and a video, preferred by the user. Yet, since it is necessary for the smart watch to have a size as small as being worn on a wrist, unlike general smart devices, it is difficult for the smart watch to have a camera. In order to enable a user to have image information using the smart watch, it is necessary to enhance the smart watch to have a camera. And, in order to more efficiently use the camera mounted on the smart watch, it is necessary to optimally control the smart watch in consideration of not only the camera but also the characteristic of the smart watch itself.